iPhone rankings vs sales

I've been tracking several applications in the MobClix rankings and comparing that data to the placement in the phone's App Store. I am, like most developers, interested in how the rankings actually work. And recently I've been wondering about the differences between ranking and placement. These are my thoughts. Your insight is appreciated.

1. The App Store's first screen under any particular category comes close to matching the actual top 25 in the rankings for that category. But beyond that the entires are sorted by something other than "sales rank". Perhaps it's purposefully done to spread the buying public's eyes across more applications and appease the myriad of developer's complaints along these lines. The Hockenberry manifesto comes to mind here. Further points address the App Store page views beyond the first screen (25) in a any particular category...

2. There seems to be precedence for newness (a recent submission). Lots of applications here with no reviews and I would imagine no sales. They usually disappear pretty quickly from the first few screens.

3. One would hope that negative reviews would bring down placement. But this doesn't seem to be the case. For example, iBeer, iHunt, Dark Knight, and all of the DS Effects products.

4. I'm starting to suspect that pushing updates somehow improves ranks and/or placement. Beyond my own disappointment that people are releasing unfinished product, they also seem to be holding onto placement by publishing updates. Perhaps all downloads, even updates, count into placement?

5. Views. Perhaps application description page views are involved in ranking? This might explain how new applications seem to hold placement for a while even while they aren't getting reviews (or sales).

6. I routinely see repeats in the rankings. Unclear what is the cause of this. Perhaps it's evidence that it's not ranking driven.